SIP Bugfix Requires SIPServer Upgrade

The fix for Launchpad Bug 1542495: "OpenILS::SIP::clean_text() can
crash" requires that you also upgrade SIPServer with the fix for
Launchpad Bug 1463943: "Non-ascii Unicode characters in messages cause
SIP client problems." This means that if you use SIP2 with Evergreen,
you must also upgrade SIPServer to the latest commit in the Git
repository. Conversely, if you upgrade SIPServer to the latest commit
in Git, you must also upgrade Evergreen or, at least, apply the patch
for Launchpad Bug 1542495. These two patches are complementary and
cannot be applied independently of one another.